[Exim] special configuration...

Hello

It is possible to configure Exim to deliver with an adress like this:

someone@???

where : someone : don't mind
             login : is the name of the emailed person in the domain
             domain.net : the domain

I would like to configure Exim to deliver the mail in the 'login' path :

eg: mail to : jack@???

will arrive to domain.net and the mail will be put in
/var/spool/mail/houston/..
ps: the localpart can be anything, only the 'login' is important.

I hope someone will help me.

Laurent Luyckx